We analyze Neuberger’s double pass algorithm for the matrix-vector multiplication R(H) · Y (where R(H) is (n − 1, n)-th degree rational polynomial of positive definite operator H), and show that the number of floating point operations is independent of the degree n, provided that the number of sites is much larger than the number of iterations in the conjugate gradient. This implies that the ma...

The size and length effects of an inclusion on multi-pass copper shaped-wire drawing were investigated. For this purpose, an experimental investigation on optimal die half-angle was conducted. Based on experimental data of optimal die half-angle, wire and inclusion deformations, drawing and hydrostatic stress of copper shaped-wires that contain an inclusion were calculated by two-dimensional fi...

AIM To evaluate the accuracy of spherical equivalent (SE) estimates of a double-pass system and to compare it with retinoscopy, subjective refraction and a table-mounted autorefractor. METHODS Non-cycloplegic refraction was performed on 125 eyes of 65 healthy adults (age 23.5±3.0 years) from October 2010 to January 2011 using retinoscopy, subjective refraction, autorefraction (Auto kerato-ref...

We demonstrate high speed force-distance mapping using a double-pass scheme. The topography is measured in tapping mode in the first pass and this information is used in the second pass to move the tip over the sample. In the second pass, the cantilever dither signal is turned off and the sample is vibrated. Rapid (few kHz frequency) force-distance curves can be recorded with small peak interac...

In the present study, thermal and thermohydraulic characteristics of different types double pass solar air heaters (DPSAHs) containing three flow channels were analytically investigated. The analyses conducted at mass rates 0.01, 0.015, 0.025 kg/s reflux ratios 0.1 to 1. effects upstream downstream recycling patterns analyzed. Moreover, impacts matrix placed between absorber plate second glass ...

In this paper, wide-angle infrared perfect absorption has been demonstrated by using a double-layer graphene strip grating coupled with silicon dioxide grating. Numerical simulation of the finite-difference time-domain method indicates that can be achieved due to effective impedance matching, and all incident electromagnetic energy is confined in Al 2 O 3 layer between silver substrate Dual-ban...

A recent study has shown that the double-pass method provides a good estimate of the ocular modulation transfer function (MTF) but that it does not yield the phase transfer function (PTF) [J. Opt. Soc. Am. A 12, 195 (1995)]. Therefore, one cannot recover the true retinal point-spread function (PSF). We present a modification of the double-pass method to overcome this problem. The key is to brea...

A high-performance AlGaInAs quantum-well saturable absorber is developed for passively Q-switched Er-Yb double-clad fiber lasers at 1560 nm. With an incident pump power of 13.5 W, an average output power of 1.26 W with a pulse repetition rate of 12 kHz is obtained. The maximum peak power is greater than 500 W.

We present a broadband microwave metamaterial (MM) absorber, the unit cell of which consists of a lumped-resistor-loaded electric-inductive-capacitive (ELC) resonator and a cut-wire on the same side of a flexible polyimide substrate. In contrast to the common MM absorber, the metallic pattern layer of the proposed structure is placed parallel to the direction of propagation of the incident wave...